The size refers to the gallons of wastewater the system can process in a day, not the capacity of the septic tank. The state standard is for systems that can process up to 10,000 gallons a day.

Typical residential septic tanks range in size between 750 gallons to 1,250 gallons. For example, a 1,000-gallon septic tank would be needed for a three-bedroom home that is less than 2,500 square ...

— 1,000-gallon septic tanks are advised for a home with three or four bedrooms. ... (which is more likely to happen if you don’t service it) could cost between $5,000 and $15,000.

A 1,000-gallon septic tank, which is an appropriate size for a three- to four-bedroom home, will cost $900 to $1,500; installation costs will bring it up to $1,500 to $4,000. Frequently Asked ...